1. Field of the Invention
The present invention relates to a light emitting device.
2. Description of the Related Art
One of the well-known light emitting devices is drawn in FIGS. 3 and 4 of Patent Document (Japanese Patent Application Publication No. 2004-221529). The light emitting device described in Patent Document includes a sapphire substrate, and a laminate structure composed of a GaN buffer layer, a non-doped GaN layer, a Si-doped GaN layer (n-type contact layer), a Si-doped GaN layer (n-type clad layer), an InGaN layer (active layer), a Mg-doped AlGaN layer (p-type clad layer) and a Mg-doped GaN layer (p-type contact layer) which are laminated in series on a surface of the sapphire substrate. The p-type contact layer, the p-type clad layer, the active layer, the n-type clad layer and the n-type contact layer are partially removed, and an n-side electrode is formed on an exposed surface of the n-type contact layer. Moreover, a p-side electrode is formed on the p-type contact layer.
The p-side electrode is composed of a p-side current diffusion portion (p-side transparent electrode layer) having translucency, and a p-side pad portion, which is formed at a predetermined portion of the p-side current diffusion portion and does not have translucency. A plurality of openings (through holes) are formed in the p-side current diffusion portion. The openings are formed in order to allow light extraction while reducing the electric resistance of the p-side current diffusion portion even when the p-side current diffusion portion is formed to have a thickness to lose translucency.